Reminder emails in email programs

I am sending a lot of on-off emails (eg. product release info). The recipients are unfortunately manually created each time and uploaded into each program. Is there a smart way to send reminder emails (read: send the same email again) automatically to the recipients who has not opened their email in, say 2 weeks?

This is a risky tactic since “opens” is such an unreliable metric. You may be resending emails to folks who indeed opened the email, but didn’t trigger the tracking pixel since they have images disabled in their email client.

I'm aware of the risky tactic, and my rational here is that in some cases the benefit of having more people opening/reading/taking action due to a reminder email, outweigh the risk of some people receiving the email twice. Ideally I would like to change the reminder email slightly, such as adding "Already signed up? Great, see you there!" - I guess the easiest way is to clone the original email and just make these changes to the reminder email?

I also have added an additional trigger in the smart list: "Clicks link in email" is not = [the email]I'm thinking this should remove some more people who clicked the link but did not download images, from wrongfully receiving the reminder email. Does this make sense?

On a broader note, IS there a way around this "opens" issue, at all? Or are there some public statistics on how skewed the 'open rate' is?